Apparatus for making fibrous cement sheet material



A. MAGNANl April 8, 1952 APPARATUS FOR MAKING FIBROUS CEMENT SHEET MATERIAL Filed NOV. 2'7, 1940 3 Sheets-Sheet 1 INVENTOR m M r 4 ATTORNEYS A. MAGNANI April 8, 1952 APPARATUS FOR MAKING FIBROUS CEMENT SHEET MATERIAL Filed Nov. 27, 1940 5 Sheets-Sheet 2 ATTORNEYS A ril 8, 1952 A. MAGNANI 2,592,518

APPARATUS FOR MAKING FIBROUS CEMENT SHEET MATERIAL Filed Nov. 27, 1940 s Sheets-Sheet 5 Patented Apr. 8, 1952 APPARATUS FOR MAKING FIBROUS CEMENT SHEET MATERIAL Alessandro Magnani, Broni, Italy Application November 27, 1940, Serial No. 367,476 In Italy September 8, 1939 4 Claims.

This invention relates to the manufacture of a fibrous cement sheet of indefinite length by depositing aqueous fibrous cement material upon a traveling pervious belt in contact with a moving suction support, the deposited material being then: molded to sheet form and the sheet compressed. More particularly, the invention is concerned with novel means for use in such apparatus for depositing and distributing the aqueous material and forming the sheet therefrom.

The distributing and sheet forming device of the invention has the form of an open center frame including side and end walls, and at least one of the end walls acts as a spreader. The device is constructed to confine av body of the aqueous material of substantially greater depth than the thickness of the sheet to be produced and the confined body of material rests upon a transverse section of a pervious sheet in contact with a suction support and extends from one side edge of the sheet to the other. Preferably, the pervious sheet is a belt and the suction support is formed by means of an endless movable series of connected hollow boxes with pervious tops, the series having an upper horizontal stretch, the boxes in which are evacuated through the supports therefor. A form of the new distributing device for use in such apparatus has a pair of Spreaders, which are preferably rolls, and the device is reciprocated lengthwise of the belt, so that the aqueous material is so distributed as to form a sheet built up of overlapping sections. The aqueous material is supplied to the device through a hose having a nozzle and, when the device is of the reciprocating type, the nozzle is caused to move back and forth with the device and also to reciprocate transversely of the belt.

For a better understanding of the invention, reference may be made to the accompanying drawings, in which Fig. 1 is a side elevational view, with parts broken away, of a fibrous cement sheet forming apparatus provided with the new distributing device:

Fig. 2 is a plan view with parts broken away of the apparatus shown inFig. 1;

Fig. 3 is a sectional view on the line 3-3 of Fig. 2;

Fig. 4 is a view in perspective of part of the suction support employed in the apparatus;

Figs. 5 and 6 are diagrammatic perspective and longitudinal sectional views, respectively, of one form of the distributing device;

Figs. 7 and 8 are diagrammatic perspective and 2 longitudinal sectional views, respectively, of another form of the distributing device; and

Figs. 9 and 10 are diagrammatic perspective and longitudinal sectional views, respectively, of another form of the distributing device.

'The sheet forming apparatus shown in Fig. 1 comprises a framework ll, near opposite ends of which are mounted bearings for shafts l2, l3 carrying wheels M. An endless series of connected hollow boxes 15 is trained about wheels 14, and the top surface [Ea of each box is formed with a multiplicity of perforations. The sectional shape of the top surfaces of the boxes defines the profile of the bottom surface of the fibrous cement sheet to be produced, and, as the apparatus illustrated is for producing a longitudinally corrugated sheet, the top surfaces i5a of the boxes, accordingly, have corrugations extending lengthwise of the series. The bottom of each box is provided near each end with a bottom opening in the form of a slot [6, the slots extending lengthwise of the series of boxes. Each box is also provided with a transverse channel in one end wall at the lower end thereof, and a bar [1 of rubber is mounted in the channel to project slightly beyond the surface of the end wall, in which the channel is formed.

The boxes in an upper stretch i8 of the series are supported with their top surfaces horizontal and, for this purpose, the boxes in the stretch rest upon the tops of a pair of chambers [9, which have longitudinal slots 20 in their top surfaces in position to register with slots IS in the bottoms of the boxes. The boxes in a lower horizontal stretch 2| of the series are supported on rails 22 attached to the framework. The boxes in the stretch [8 form a suction support and, in the operation of the apparatus, the support is moved to the right (Fig. 1) by rotation of the wheels [4 on shaft 13. For this purpose, the shaft is driven through a gear reduction box 23 by a motor 24.

A belt 25 of water-pervious fabric encircles the series of boxes and lies in contact with the top surfaces of the boxes in the upper stretch l8. In order that the belt may fit the corrugated top surfaces of the boxes, the belt is acted on by upper and lower sets of rollers 28, 21 mounted on respective shafts 28,, 29 supported in brackets attached to the framework. Rollers 26 are offset fromrollers 21 and shafts 28, 29 are so spaced that the belt is given a corrugated form as it passes between the rollers in the two sets. The belt continues beyond the end of stretch I8 and passes over a fixed support 30 and then turns .horizontal guides 56.

abruptly around an angle bar 3|, which has corrugations on its top and side surfaces, over which the belt travels. Beyond the angle bar, the belt passes about idler rollers 32, 33, and 34, which are cylindrical, so that the belt is flattened. Material adhering to the belt may be cleaned therefrom by a nozzle 35 directing jets of water against the belt at an appropriate place;

One form of the new distributing device, generally designated 36, is mounted to overlie the belt close to the place where the belt moves into contact with the top of the boxes in stretch l8, and the distributing device includes side walls 37, in which are mounted shafts 33, 39. Each shaft is provided with a pair of flanged rollers 40 running on guides 41, which are supported to lie on opposite sides of the'belt and the boxes in the upper stretch. Each guide has end sections ilo with horizontal top surfaces and an intermediate section Mb having a top surface which inclines upwardly in the direction of travel of the belt and boxes. Between the side plates 3.1, the shafts 38 are equipped with spreaders in the form of rolls 52 having a corrugated shape conforming to the shape of the corrugations in the tops of the boxes and the surfaces of the rollers lie spaced a distance above the belt corresponding to the thickness of the sheet to be produced.

.A motor 43 mounted on a cross-bar 44 connecting the side plates 37 has a shaft provided with a pinion d driving a gear 46 on shaft 39. The motor is of the reversing type, and, during the operation of the apparatus, the motor drives shaft 39 first in one direction and then in the other. As a result, the distributing device is reciprocated along guides 4| as indicated by the arrow in ,Fig. 1.

The aqueous fibrous cement material is delivered to the distributing device through a hose 4'! provided with a nozzle 46, which enters, a

slot 490. in a guide as attached to stationary in the device is spread out by rollers 42 during the reciprocation of the device to form a sheet S. and the material and the sheet made therefrom are continuously dewatered until the belt,

on which the sheet rests, loses contact with the boxes !5.

The dewatering of the material and sheet is cllected by evacuating the boxes in the upper stretch I8, and, for this purpose, the chambers 19 are connected to a vacuum pump through lines 19a. Suction is thus applied to the boxes through the slots 26 at the top of chambers 19 and the bottom openings 16 of the boxes in the upper stretch I8.

After passing beyond the. limit of travel of the distributing device, the sheet is compressed by means of a corrugated pressure roll 5| mounted on a shaft 52 on a carriage 53. The carriage is provided with a second shaft 54 and shafts 52 and 55 carry flanged wheels 55 running on A motor 51 mounted on the carriage has a pinion 58 on its shaft meshing with a gear 55 on shaft 52, and the motor is o! the reversing type, so that, during the operation of the apparatus, it rotates shaft 52 first in one direction and then in the other. As a result, the carriage reciprocates on the guides lengthwise of the direction of travel of the boxes and belt. Roller 5! is set to bear on the sheet S with the desired pressure.

The distributing device. 36 has the form of an open center frame, of which the plates 31 form the side walls and rollers 42 form the end walls, and the height of the frame is such that it can confine a body of fibrous cement material in contact with the belt, the body having a depth substantially greater than the thickness of the sheet to be produced. The rollers act as spreaders and distribute the material and roll it into sheet form, as the device 36 reciprocates lengthwise of the direction of travel of the boxes and belt, but, if desired, the distributing device may remain at rest, while the suction support and belt move beneath it. Alternatively, the suction support and belt may remain at. rest and the distributing device may move along the support and belt or the device may move in one direction, while the support and belt are moving in the opposite direction. A form of distributing device for the latter purposes is shown in Fig. 5 as including a frame 60 having side walls 6!, a fixed end wall 62, and a spreading roller 63 mounted in walls BI and lying spaced from wall 62'. The frame is suitably mounted above that portion of belt 64 lying in contact with the suction support 65, and the aqueous fibrous cement material is delivered into the interior of the frame by a nozzle 66. When the distributing device has the form shown in Fig. 5, the device may move in the direction of the arrow (Fig. 6), while the belt 64 and suction support 65 remain at rest or move in a direction opposite to that of the frame. If preferred, the frame may remain at rest and the belt and suction support may move in a direction opposite to that of the arrow in Fig. 6.

Instead of employing a roller, such as roller 63, for spreading the material, the spreading may be effected by means of a plate 61 mounted between the side walls 68 of a frame 69 and in spaced relation to a fixed end wall 10. of the frame as shown in Figs. '7 and 8. The lower edge of the plate is spaced above the belt H, on which the fibrous cement material is to be distributed by the plate.

The distributing device 12 shown in Figs. 9 and 10 is similar to the device 36, in that it includes side walls 13 and a pair of spreaders .mounted in the side walls and lying in spaced relation. In device 72, these spreaders are inclined plates 14 similar to plate 67. The distributing device I2 is intended for reciprocation in the same manner as device 36.

In the operation of all forms of the distributing device, the fibrous cement material is preferably supplied at such a rate that a body 15 of the material is confined within the device in contact with the belt resting upon the suction support. The body of fibrous cement-material thus confined is substantially thicker than the sheet S to be produced and extends from side to side of the area of the belt, on which the sheet is to be formed. By confining such a body of material in contact with the belt, the confined material is continuously subjected to dewatering and the device produces a sheet of uniform thickness.

I claim:

1. In apparatus for the manufacture of fibrous cement sheet material, the combination of a suction support having a pervious horizontal top, a strip of pervious fabric covering the support, a frame overlying the portion of the strip in contact with the support and extending across the strip, the frame including side walls and a pair of spaced transverse spreading elements having lower edges spaced from the surface of the strip, means for moving the strip and support to advance the strip beneath the frame, guides along the sides of the support, the guides having horizontal end sections and intermediate sections inclined upwardly in the direction of movement of the strip and support and the frame having rollers running on the guides, means for reciprocating the frame on the guides, and means for depositing aqueous fibrous cement material on the strip within the frame.

2. In apparatus for the manufacture of fibrous cement sheet material, the combination of a suction support having a pervious horizontal top, a strip of pervious fabric covering the support, a frame overlying the portion of the strip in contact with the support and extending across the strip, the frame including side walls and a pair of spaced transverse spreading elements having lower edges spaced from the surface of the strip, means for moving the strip and support to advance the strip beneath the frame, means for reciprocating the frame lengthwise of the path of travel of the strip and support, means, including a nozzle, for depositing aqueous fibrous cement material on the strip within the frame. and means mounted on the apparatus and opera tively connected to actuating mechanism for moving the nozzle with the frame and back and forth transversely of the strip, as the frame reciprocates.

3. In apparatus for the manufacture of fibrous cement sheet material, the combination of a suction support having a pervious horizontal top, a strip of pervious fabric covering the sup port, a frame overlying the portion of the strip in contact with the support and extending across the strip, the frame including side walls and a pair of spaced transverse spreading elements having lower edges spaced from the surface of the strip, means for moving the strip and support to advance the strip beneath the frame, means for reciprocating the frame lengthwise of the path of travel of the strip and support, means, including a nozzle, for depositing aqueous fibrous cement material on the strip within the frame, and a pair of guides, one on the frame and the other stationary, for moving the nozzle with the frame and back and forth transversely of the strip, as the frame reciprocates.

4. Apparatus as defined in claim 3 in which said guides are positioned over the strip and support and have slots extending at an acute angle to one another, one slot extends over the other and a portion of the means for depositing aqueous fibrous cement material on the strip within the frame extends through the slots in the guides at the point where one slot extends over the other.

ALESSANDRO MAGNANI.

REFERENCES crrnn The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 766,461 McFarland -1 Aug. 2, 1904 2,041,967 Schroder et al May 26, 1936 2,297,564 Salvaneschi Sept. 29, 1942 FOREIGN PATENTS Number Country Date 455,601 Great Britain Oct. 19, 1936 829,372 France June 24, 1938 374,936 Italy Sept. 18, 1939 376,993 Italy Dec. 4, 1939 379,889 Italy Apr. 11, 1940 

